Articulated metal shell for an electric hot-pad.



H. D. LARAWAY 61 B. FALKENBERG.

ARTICULATED METAL SHELL FOR AN ELECTRIC HOT PAD.

APPLICATION FILED SEPT. 6. 19I6.

Patented Sept. 18, 1917.

UNITED STATES PATENT OFFICE.

HENRY D. LARAWAY AND BJ'ARNE FALKENBERG, OF ONTARIO, CALIFORNIA, AS-

SIGNORS TO HOTPOINT ELECTRIC HEATING COMPANY, OF ONTARIO, CALIFORNIA,

A CORPORATION OF CALIFORNIA.

Specification of Letters Patent.

Patented Sept. 18, 1917.

Application filed September 6, 1916. Serial No. 118,779.

To all whom it may concern:

Be it known that we, HENRY D. LARAWAY, a citizen of the United States, and BJARNE FALKENBERG, a subject of the King of Norway, both residing at Ontario, in the county of San Bernardino and State of California, have invented a new and useful Articulated Metal Shell for an Electric Hot-Pad, of which the following is a specification.

Our invention relates to the art of electric heating, and more especially to hot pads which are used in the sick room, and as articles of personal comfort.

The principal object of the invention is to rovide a hot pad which will be entirely inc osed in an articulated metal shell which can be bent into various curvatures so that it can be applied to various portions of the body.

It is common practice in the art to inclose a. heating element in a rigid metallic shell,

this shell being inclosed in a suitable fabric and used for the same purpose that an ordinary rubber hot water bag is used. Such rigid metal shells are not as satisfactory as the rubber hot water bag, as the rigid metal covers cannot be bent to adapt them to the curvature of the body of the person using them. By articulating the metal cover all of the advantages of the rigid metal cover are obtained, and in addition the pad can be bent to adapt itself to various uses.

v The internal construction of the pad forms no part of the present invention, and will be described only briefly.

- Referringto the drawings, which are for illustrative purposes only:

Figure 1 is a view of our invention, a portion thereof being broken away to better show the internal structure.

Fig. 2 is a side view of our invention, one of the methods in which the pad can be bent being shown in dotted lines.

Fig. 3 is an enlarged section on a portion of a plane represented by the line m -m-' in Fig. 1, this plane being viewed in the direction of the arrows.

Fig. 4 is a section on the same scale of the plane represented by the line w*-w of Fig. 1, this plane being viewed in the direction of the arrows.

Fig. 5 is a perspective view showing the tric heating elements 11 are placed between two sheets of flexible insulating material 12 and 13, being secured therein by eyelets 10. The heating elements 11 are connected to a' flexible cord 14 which passes through a stamping 15 secured to a head 16. A spiral spring 17, and an insulating button 18 are provided in accordance with standard practice in heating devices to prevent the cord 14 from being broken off close to the stamping 15. The head 16 forms the first element of the articulated metal shell, this head being formed of a piece of sheet metal bent at right angles on the lines 19 and 20 to form an upper portion 21, a lower portion 22, and an end 27. The upper portion 21 and the lower portion 22 are bent over on the lines 23 to form side members 24 and 25. A small tongue 26 is formed on the end 27. Formed on the side 24 is a small flange 28, and formed on the side 25 is a small flange 29. The flange 29 is of suitable size to be crimped over the flange 28 when the shell is completely assembled, the method of crimping being shown in Fig. 4. The corrugated depression 30 is formed in the top 21 and the bottom 22, this depression serving to form a portion of a cylindrical end 31 when the shell is properly secured together by crimping the flanges 28 and 29 together. The remainder of the articulated shell is formed on a series of metal members 32, each of these members having two depressions 33 which form cylindrical Corrugations 34, these corrugations being well illustrated in Fig. 5. The upper one of the members 32 is'provided with a short flange 35, and the lower of the members 32 is provided with a long flange 36, the flange 36 crimping over the flange 35 to secure the two members 32 together as shown at the extreme right of Fig. 5. The openings 37 are left at either end of the assembled members, and the extreme outer opening is closed by a semi-cylindrical punching 38.

The method of assembling the various members is as follows:

An upper member 32 and a lower member 32 are secured together as shown at the extreme right of Fig. 5, the small cylindrical punching 38 being placed in position therein. The flanges 35 and 36 are then crimped together, these flanges having small depressions 39 which prevent the members 32 from shifting with relation to each other after the flanges are crimped. A second pair of members 32 is then assembled, the right hand cylindrical portion of this new set being placed over the left hand cylindrical portion of an adjacent set. The flanges 85 and 36 are then crimped together, the parts assuming the position shown in section in Fig. 3. This process is continued until all of the members 32 are assembled forming a sort of an inclosed box with one end open. The heating elements 11 and their inclosing insulation 1:2 are then secured in place in the head 16, suitable connections being made to the cord 14, and the top 21 and the bottom 22 of the head 16 are then closed down on the end of the box previously formed by the members 32, and the flanges 28 and 29 are crimped in place. The result of this structure is an articulated metal case or cover which completely surrounds the heating elements 11, protects them firom mechanical injury and protects the user from excessive temperatures.

In the actual application of the invention, suitable switches, and thermostatic devices, may be assembled in the head 16, if desired, but as they form no part of the present invention all reference to them is omitted from the present specification.

We claim as our invention 1. A hot pad comprising a heatmg element, and a metal shell inclosing said element, said shell being composed of a series of sections locked together but having a limited movement with relation to each other.

2. In a hot pad, an articulated metal shell comprising a series of sheet metal members so formed that they mutually engage each other and have a limited movement with relation to each other.

3. In a hot pad, an articulated metal shell comprising a series of sheet metal members each bent to form a series of parallel partial cylinders, and means for securing one of said partial cylinders on one of said series of sheet metal members around a similar partial cylinder of an adjacent one of said series of sheet metal members.

4. In a hot pad, an articulated metal shell comprising a series of sheet metal members each bent to form a series of parallel partial cylinders, and means for securing one of said partial cylinders on one of said series of sheet metal members around a similar partial cylinder of an adjacent one of said series of sheet metal members in such a manner that the two sheet metal members so fastened together have a limited angularmovement with relation to each other.

5. In an articulated metal shell, a pair of sheet metal members each comprising a series of corrugations, each corrugation forming a portion of a cylinder, sides bent down approximately at right angles to the axis of said cylinders, and means for securely locking the sides of one of said pair of members to the sides of the other of said pair of members.

6. In an articulated shell, a series of metal members each formed of a pair of depressed portions which separate and assist in formmg a series of parallel cylindrical surfaces.

7. In a hot pad, a head formed of sheet metal, a series of sheet metal members articulated together to form a box, said sheet metal members being articulated to said head, and a heating-element secured in said head and projecting into said box.

8. In a hot pad, a head formed of sheet metal, a series of sheet metal members articulated together to form a box, said sheet metal members being articulated to said head, and a flexible heating element secured in said head and projecting into said box.

9. In a hot pad, an articulated metal shell comprising a series of sheet metal members each bent to form a series of parallel corrugations, and means for securing one of said corrugations on one of said series of sheet metal members over a corrugation of an adjacent one of said series of sheet metal members.

10. In a hot pad, an articulated metal shell comprising a series of sheet metal members each bent to form a series of parallel corrugations and means for securing one of said corrugations on one of said series of 

